Employee Incentive Plans - Restricted and Performance Awards (Details) - USD ($) $ / shares in Units, $ in Millions		1 Months Ended			3 Months Ended
	Jul. 23, 2018	Mar. 31, 2020	Feb. 29, 2020	Jan. 31, 2020	Mar. 31, 2020	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Grant-Date Fair Value (in dollars per share)		$ 1.13		$ 7.69
Beginning TSR Price (in dollars per share)		$ 1.25		$ 6.13
Risk-free interest rate		0.42%		1.62%
Volatility factor		51.00%		37.00%
Unvested restricted units
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Non-vested, beginning of period (in shares)				4,063,605	4,063,605
Granted (in shares)			1,144,842		4,554,493
Vested (in shares)					(1,978,817)
Forfeited (in shares)					(53,105)
Non-vested, end of period (in shares)		6,586,176			6,586,176
Aggregate intrinsic value, end of period		$ 7.2			$ 7.2
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Non-vested, beginning of period (in dollars per share)				$ 13.85	$ 13.85
Granted (in dollars per share)					5.66
Vested (in dollars per share)					9.56
Forfeited (in dollars per share)					11.34
Non-vested, end of period (in dollars per share)		$ 9.50			$ 9.50
Fair value of units vested			$ 5.2
Units withheld for payroll taxes (in shares)					732,473
Vesting period					3 years
Unrecognized compensation cost related to non-vested restricted incentive units		$ 37.3			$ 37.3
Unrecognized compensation costs, weighted average period for recognition					1 year 10 months 24 days
Unvested restricted units | ENLC
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Fair value of units vested					$ 18.9	$ 12.6
Aggregate intrinsic value of units vested					$ 10.1	12.4
Unvested restricted units | EnLink Midstream Partners, LP
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Fair value of units vested						7.2
Aggregate intrinsic value of units vested						8.0
Performance units
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Non-vested, beginning of period (in shares)				1,317,856	1,317,856
Granted (in shares)					1,161,986
Vested (in shares)					(160,002)
Non-vested, end of period (in shares)		2,319,840			2,319,840
Aggregate intrinsic value, end of period		$ 2.6			$ 2.6
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Non-vested, beginning of period (in dollars per share)				$ 14.22	$ 14.22
Granted (in dollars per share)					7.32
Vested (in dollars per share)					31.13
Non-vested, end of period (in dollars per share)		$ 9.60			$ 9.60
Fair value of units vested					$ 5.0	1.9
Units withheld for payroll taxes (in shares)					60,920
Aggregate intrinsic value of units vested					$ 0.9	1.8
Unrecognized compensation cost related to non-vested restricted incentive units		$ 16.8			$ 16.8
Unrecognized compensation costs, weighted average period for recognition					1 year 9 months 18 days
Performance units | Minimum
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Percent of units vesting	0.00%				0.00%
Performance units | Maximum
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Percent of units vesting	100.00%				200.00%
Performance units | EnLink Midstream Partners, LP
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Fair value of units vested						1.7
Aggregate intrinsic value of units vested						$ 2.1
Compensation expense not yet recognized		0.7			$ 0.7
ENLC Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Compensation expense not yet recognized		$ 2.1			$ 2.1